Effect of Local Administration of Brain Derived Neurotrophic Factor with Silicone Conduit on Peripheral Nerve Regeneration: a Rat Sciatic Nerve Transection Model

Abstract

Objective- The objective was to assess local effect of brain derived neurotrophic factor (BDNF) on functional recovery of peripheral nerve in rat sciatic nerve transection model. Design- Experimental study. Animals- Sixty male healthy white Wistar rats Procedures- The animalswere randomized into four experimental groups of 15 animals each: In sham-operated group (SHAM), sciatic nerve was exposed and manipulated. In transected group (TC), left sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. In silicone graft group (SIL) a 10-mm defect was made and bridged using a silicone tube. The graft was filled with phosphated-buffer saline alone. In treatment group the silicone tube (SIL/BDNF) was filled with 10 microliter BDNF (100ng/kg BW). Each group was subdivided into three subgroups of five animals each and regenerated nerve fibers were studied at 4, 8 and 12 weeks post operation. Results- Behavioral testing, sciatic nerve functional study, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in SIL/BDNF than in SIL group (p < 0.05). Immunohistochemical study showed clearly more positive location of reactions to S-100 in SIL/BDNF than in SIL group. Conclusion and Clinical Relevance- When loaded in a silicone graft, BDNF improved functional recovery and morphometric indices of sciatic nerve. This finding supports the role of BDNFafter peripheral nerve repair and may have clinicalimplications for the surgical management of patientsafter nerve transection.